1. Technical Field
Embodiments of the invention generally relate to micromachined transducer arrays, and more particularly, but not exclusively, pertain to techniques for wafer level fabrication of such arrays.
2. Background Art
A piezoelectric transducer includes a piezoelectric element capable of converting electrical energy into mechanical energy (e.g., motion, sound or ultrasound energy), and vice versa. Thus, a piezoelectric transducer can serve both as a transmitter of mechanical energy and a sensor of impinging mechanical energy. A piezoelectric element can be used as an actuator, inkjet membrane, ultrasound transducer, sensor (e.g. accelerometer, gyro, pressure sensor, etc.) or other device for energy harvesting, mixing, pumping or any of various other applications.
Transducer devices can be advantageously fabricated inexpensively to exceedingly high dimensional tolerances using various micromachining techniques (e.g., material deposition, lithographic patterning, feature formation by etching, etc.). Such devices include micromachined transducer arrays such as arrays of capacitive transducers and/or piezoelectric transducers, for example. Typically, piezoelectric structures of a transducer array are built on a semiconductor wafer which is subsequently cut into die which are variously incorporated each into a respective device.